Currently, There are almost 99% bacteria can not to be found with bacterial culture. Based on microscopy and conventional culture method to obtain vaginal microflora information have a variety of deviation. For this reason, The in-depth study of complex vaginal flora and the correct understanding of disease faces a serious obstacle. With the development of High-throughput sequencing technology， metagenomics can get all the composition and distribution of microorganisms from the sample which traditional knowledge may not be with microorganism culture method. Therefore, Re-evaluation of existing microflora diagnostic criteria for clinical diagnosis of the disease is necessary.